APPORTIONMENT OF NON-PIXE SPECIES BY MEANS OF PIXE ANALYSIS

Source apportionment for air pollution by means of receptor models are often used in connection with PIXE analysis. The origin of ''non-PIXE '' species is assessed mainly by using PIXE based models. Three case s tudies are discussed. 1) Soot is often used as general indicator for a nthropogenic air pollution. The trend in the source contributions are evaluated by including the measurements of soot on equal terms with mu ltielement measurements in a factor model. Long range transport seems to be the main reason for the increasing concentrations of soot in the beginning of the 1980s. 2) A regression analysis is performed between campaign measurements of the mutagenic activity of the aerosol in the center of Copenhagen and the factor scores in a factor model based on more than one year of daily measurements of multielement concentratio n together with SO2, NO, NO2 and total particulates. It is shown that traffic is the main source at street level, but that other local anthr opogenic sources as well as long range transport contribute with compa rable amounts. 3) A multipoint receptor model is used to show that loc al sources as well as long range transport supplies the NO3- + HNO3 at two sites in the southern part of Scandinavia, while no reasonable as sessment of NO2 could be achieved.